Ethyl 3-phenylpropionate → 2-Oxo-4-phenylbutyric acid

HRID 2372589Notes

Reaction equation

HRID 2372589 reaction equation
[C:1]1([CH2:7][CH2:8][C:9]([O:11]CC)=O)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C(OCC)(=O)[C:15]([O-:17])=[O:16].[O-]CC.[Na+]>C(O)C>[O:11]=[C:9]([CH2:8][CH2:7][C:1]1[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1)[C:15]([OH:17])=[O:16]

Participants

5

Reactant 3

HCID 16237Ethyl 3-phenylpropionateHCID 2723922Sodium ethoxideHCID 21943339Ethanedioic acid, monoethyl ester

Product 1

HCID 697322-Oxo-4-phenylbutyric acidYield 90.9%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A mixture of 143 g of ethyl 3-phenylpropionate, 234 g of ethyl oxalate and 154 ml of 28% sodium ethoxide solution in ethanol is heated on a water bath at a bath temperature of 60°-70° C. for 1.5 hours, while distilling off the ethanol under reduced pressure. To the resulting red syrupy residue is added 1.3 liters of 15 v/v % sulfuric acid. The mixture is boiled under reflux with stirring for 15 hours, and the oil layer is separated, neutralized with 10% sodium hydroxide and extracted with ethyl acetate. The aqueous layer is made acidic with diluted sulfuric acid. The resulting oil is extracted with ethyl acetate, washed with water and dried. Removal of the ethyl acetate by distillation under reduced pressure gives 130 g of 2-oxo-4-phenylbutyric acid as an oil.

Workup

  1. temperatureis heated on a water bath at a bath temperature of 60°-70° C. for 1.5 hours
  2. distillationwhile distilling off the ethanol under reduced pressure
  3. additionTo the resulting red syrupy residue is added 1.3 liters of 15 v/v % sulfuric acid
  4. temperatureunder reflux
  5. customthe oil layer is separated
  6. extractionextracted with ethyl acetate
  7. extractionThe resulting oil is extracted with ethyl acetate
  8. washwashed with water
  9. customdried
  10. customRemoval of the ethyl acetate
  11. distillationby distillation under reduced pressure

Sources & evidence

ORD record
ord-30efbec1f80e4ff6b18e42c713e1e820
Source dataset
uspto-grants-1992_03
Patent number
US05098892

Reaction notes

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